Electric-arc lamp



(No Model.)

B. SEGERDAHL.

. ELECTRIC ARC LAMP.

No. 528,184. Patented Oct. 30, 1894..

UNITED STATES PATENT OFFICE.

RUDOLPH SEGERDAHL, OF CHICAGO, ILLINOIS.

ELECTRIC-ARC LAM P.

SPECIFICATION forming part of Letters Patent No. 528,184, dated October30, 1 894.

Application f led February 26, 1894. Serial No. 501.489- (No model.)

To aZZ whom it may concern.-

Be it known that I, RUDOLPH SEGERDAHL, a

citizen of the United States, residing at Chicago, in the county of Cookand State of Illinois, have invented a new and useful Improvement inElectric Lamp Rheostats, of which the following is a specification.

My invention relates to that class of rheo stats used in connection witharc lamps, and more particularly to a method of securing said rheostat(or resistance) to the lamp structure. Ordinarily this resistanceisarranged in a box separate from the lamp and placed in any suitableplace in the main circuit. In other instances, the required amount ofresistance is arranged inside a casing secured to the lamp structure.

The objection against the first mentioned method is the general one madeagainst inclosed resistances byfire-underwriters; and to the othermethod, the objectionable appearance of a large casing attached to thelamp structure.

The objects of my improvement are, first, to provide means whereby theresistance may be attached to the lamp structure without disfiguring thegeneral appearance of the lamp; second, to obviate accidents from fire,which are liable to occur when a resistance within an inclosure is used;third, to obtain a cheap and durable structure and which is readilyattached to the lamp. I attain these obj ccts by the mechanismillustrated in the accompanying drawings, in which Figure 1, is a planeelevation of a lamp embodying my improvements, and Fig. 2, amodification showing the resistance secured to the side rods of thelamp-frame.

Similar letters referto similar parts throughout both the views.

In Fig. 1, --A-- is ahanging board or crosspiece in connection with thetop of the lamp B and adapted to sustain the weight of the same. To thiscross bar are fastened binding posts a-a which are insulated from oneanother and arranged to clamp the circuit wires -bb'. The resistancec-cis preferably made in the form of coils and connected to thebinding-posts -a-a' on the cross bar A and to the circuit terminals d-d' of the lamp -B-.

In Fig. 2, I have shown the resistance wound around the side rods e ofthe lamp. When availing myself of this method, I make the side rods assmall as possiblein diameter and provide the same with an insulatingsurface. After the resistance is placed around the same I prefer to coatthe exterior surface with enamel or any other suitable non-conductor.

Having fully described my invention, what I consider as new, and desireto secure by Letters Patent, is-

1. The combination with an electric lamp, of a cross piece --A- inconnection with or secured to said lamp and adapted to sustain theweight of the same, clamps aa arranged to receive the circuit terminalsbb-, and a resistance c-c consisting of two parts, connectedrespectively to said circuit terminals and lamp terminals and formingapart of the circuit on each side of the lamp, substantially as and forthe purpose described.

2. The combination with an electric arc lamp provided with means adaptedto sustain the weight of the same, of a resistance cc-- consisting oftwo parts, interposed betweenthe circuit terminals and lamp terminalsrespectively'and secured to or located on each side of the framestructure of said lamp.

RUDOLPH SEGERDAHL.

Witnesses:

JOHN SHILLESTAD, CASSIUS M. 0. (Ross.

